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Paranthropus
The robust australopithecines, members of the extinct hominin genus Paranthropus (Greek para "beside", Greek anthropos "human"), werebipedal hominids that probably descended from the gracile australopithecine hominids (Australopithecus). Discovery A partial cranium and mandible of Paranthropus robustus was discovered in 1938 by a schoolboy, Gert Terblanche, at Kromdraai B (70 km south west of Pretoria) in South Africa. It was described as a new genus and species by Robert Broom of the Transvaal Museum. The site has been excavated since 1993 by Francis Thackeray of the Transvaal Museum. A date of at least 1.95 million years has been obtained for Kromdraai B. Paranthropus boisei was discovered by Mary Leakey on July 17, 1959, at the FLK Bed I site of Olduvai Gorge in Tanzania (specimen OH 5). Mary was working alone, as Louis was ill in camp. She rushed back to camp and at the news Louis made a remarkable recovery. They refrained from excavating until Des Bartlett had photographed the site. In his notes Louis recorded a first name, Titanohomo mirabilis, reflecting an initial impression of close human affinity. Louis and Mary began to call it "Dear Boy". Recovery was halted on August 7. Dear Boy was in context with Oldowan tools and animal bones. The fossil was published in Nature dated August 15, 1959, but due to a strike of the printers the issue was not released until September. In it Louis placed the fossil in Broom's Australopithecinae family, creating a new genus for it, Zinjanthropus, species boisei. "Zinj" is an ancient Arabic word for the coast of East Africa and "boisei" referred to Charles Boise, an anthropological benefactor of the Leakeys. Louis based his classification on twenty differences from Australopithecus. Broom had died in 1951 but Dart was still living. He is said to have wept for joy on Louis' behalf on being personally shown Zinj, which Louis and Mary carried around in a tin (later a box). Louis had considered Broom's Paranthropus genus, but rejected it because he believed Zinj was in the Homo ancestral stock but Paranthropus was not. He relied heavily on the larger size of Zinj's canines. At that time palaeoanthropology was in an overall mood to lump and was preaching against splitting. Consequently, the presentation of Zinj during the Fourth Pan-African Congress of Prehistorians in July in the then Belgian Congo, at which Louis was forced to read the delayed Nature article, nearly came to grief for Louis over the creation of a new genus. Dart rescued him with the now famous joke, "... what would have happened if Mrs. Ples had met Dear Boy one dark night." The battle of the name raged on for many years and drove a wedge between Louis and LeGros Clark, Sir Wilfrid from 1955, who took the Paranthropus view. On the other hand it brought the Leakeys and Dr. Melville Bell Grosvenor of the National Geographic Society together. The Leakeys became international figures and had no trouble finding funds from then on. The Zinj question ultimately became part of the Australopithecus/Paranthropus question (which only applied to the robust Australopithecines). Description All species of Paranthropus were bipedal, and many lived during a time when species of the genus Homo (which were possibly descended from Australopithecus), were prevalent. Paranthropus first appeared roughly 2.7 million years ago. Most species of Paranthropus had a brain about 40 percent of the size of a modern human. There was some size variation between the different species of Paranthropus, but most stood roughly 1.3-1.4 m (4 ft 3 in to 4 ft 7 in) tall and were quite well muscled. Paranthropus is thought to have lived in wooded areas rather than the grasslands of the Australopithecus.needed "Paranthropus" is thought to be bipedal based on its anatomical structure in its hips, legs, and feet that resemble both its ancestor, "Australopithecus afarensis", and modern humans.2 The pelvis is similar to "A. afarensis" but the hip joint, including the femoral head and acetabulum are smaller in "Paranthropus". The similar hip structure between "A. afarensis" and "Paranthropus" implies that they had a similar walking gait, and that "Paranthropus" moved like the 'gracile australopiths'.3 They show anatomical similarity to modern humans in the big toe of their foot and their well developed plantar aponeurosis. The hallux metatarsal shows increased base for more internal support, and more distal articular surface which causes more connection and support to the other bones in the foot.4 The extra support in the big toe and extensive plantar aponeurosis shows that "Paranthropus" had hyperextension of their toes for a 'toe-off' gait cycle, characteristic of modern bipedalism in humans. The behavior of Paranthropus was quite different from that of the genus Homo, in that it was not as adaptable to its environment or as resourceful. Evidence of this exists in the form of its physiology which was specifically tailored to a diet of grubs and plants. This would have made it more reliant on favorable environmental conditions than members of the genus Homo, such as Homo habilis, which would eat a much wider variety of foods. Therefore, because it was a specialist species, it had more difficulty adapting to a changing climate, leading to its extinction. Disputed taxonomy Category:Early species of Homo Category:Human evolution Category:Early hominids Category:Pliocene primates Category:Prehistoric mammals of Africa Category:Pleistocene primates